Azo colors suitable for use as pigments.



UNITED STATES PATENT OFFICE.

HEINRICH CLINGES'I'ETN, OF Mfi'LHEIM, NEAR COLOGNE, GERMANY, A SSIGNOR TO FARBENFABRIKEN VORM. FRIEDR. BAYER & 00., OF ELBERFELD, GERMANY, A

CORPORATION Oil? GERMANY.

AZO COLORS SUITABLE FOR USE AS PIGMEN'IS.

No Drawing.

To all who "tit may concern:

Be it known that I, Hnmmon (lamens'rum, doctor of philosophy, chemist, citizen of the German Emplre, residing at Miilheiin, near Cologne-on-the-Rhine, Germany, have invented new and useful Improvements in New Azo Colors Suitable for Use as Pigments, of which the following is a specificatlon.

My invention relates to the'manufacture and production of new azo-coloring matters which are prepared by the combination of the diazo compounds of halogenated aromatic amins, such as ortho-chloro-anilin, 2.5-dichloro-anilin, para-chloro-anilin, ortho-bromo-anilin, 2.4-dichloro-anilin, orthochloro-para-toluidin with the condensation products obtained from aceto-acetic-ester and the alkylethers of para-aminophenols e. g. para-anisidin or para-phenetidin. The new products are after being dried and pul verized yellow powders, insoluble in water, soluble in concentrated sulfuric acid with a yellow coloration. They have most prob ably the following general formula:

CH-N NR (R meaning a halogenated aromatic radical,

X meaning an alkyl group, such as GH,,, 0 H

These new dyes are particularly suitable for use as pigments. When used in the form of lakes, prepared from these dyes they possess brilliant greenish-yellow shades re plete the residue is filtered off and washe Specification of Letters Patent.

Application filed May 9, 1913. Serial N0. 766,643.

Patented Oct. 28, 1913..

with water. The dye thus obtained can be stirred to a paste. hen dried it is a pure yellow powder having most probably the formula:

The lakes can be prepared 6. 9. according to the following prescription: Mix intimately 100 parts of a finely ground heavy spar with a solution of 9.0 parts of aluminlum sulfate in 1200 parts of hot water and add thereto a boiling suspension of 6 parts of the azo dye obtained according to the first example in 1000 parts of water contaming 10 parts of anhydrous sodium carbonate, boil the mixture and add to it while it is being stirred a hot solution of 30 parts of crystallized BaGl in 300 parts Water. Boil, filter off and wash. The color of this lake is greenish-yellow. The lakes and the coloring matter can also be produced in one operation.

The hitherto unknown aceto-acetic-acidgt meaning a halogenated aromatic radical meaning an alkyl,) which are after being dried and pulverized yellow powders insoluble in water, soluble in concentrated sulfuric acid generally with. a yellow coloration; furnishing valuable greenish-yellow color lakes resembling zinc yellow which are fast to light, substantially as described.

2. As a new product the new dyestufi dewhich is after being dried and pulverized 2 yellow powder insoluble in Water, soluble in concentrated sulfuric acid with a yellow color; and furnishing valuable yellowish- -green color lakes resembling zinc yellow which are fast to light, substantially as described.

In testimony whereof I have hereunto set my hand in the presence of two subscribing Witnesses.

HEINRICH OLINGESTEIN. [Ls] Witnesses HELEN NUFER, ALBERT NUFER. 

